Aldon Smith, the 49ers' All-Pro linebacker who was arrested Friday morning on suspicion of driving under the influence and marijuana possession, is expected to play Sunday, San Francisco Coach Jim Harbaugh told reporters.

"I expect Aldon — like today — he'll be back to work and playing on Sunday," Harbaugh said. "I anticipate that, yes."

Smith, though, could be disciplined by the NFL since this is his third run-in with the law in less than two years.

Smith, who was a force as a rookie out of Missouri with 14 sacks in 2011, was arrested in Miami Beach last year on suspicion of DUI, but accepted a deal for a lesser charge. He is currently facing a lawsuit that claims he threw a party in June 2012 where weapons were discharged and a partygoer was struck in the leg with two bullets.

"There will be consequences," Harbaugh said Friday. "There always is. Good or bad, we all have consequences."

Smith, who had 19 1/2 sacks last season to help the 49ers reach the Super Bowl, was released from jail Friday after posting bail of $5,250. He attended practice in the afternoon but did not talk to reporters.

Smith was taken into custody after a 7 a.m. report of a single-car accident in San Jose, where he lives. Police said he failed a breath test during their preliminary investigation at the scene.